Sorry, I edited my comment and you may have missed it. How would you emulate multi-line closures in Python? A free function which you can pass to a higher order function is not a closure. I think you would need to create a functor, and that becomes even more verbose.
Closures are functions that can capture values/references visible in the scope where the function is defined/instantiated. They are basically a short hand way of creating function objects, functions which have data members.
I believe all functions are object in python, so you can add attributes to them, but you'd be better of creating a class with a __call__ method. Relevant scope can be captured in the class __init__.
Classes themselves can hold multiple functions/methods, and if you want a function that carries state, maybe a generator would be useful?
I think this is the point. You can do all these things, but they are all extra hoops you have to jump through when all you want/need is an anonymous on-the-spot closure.
I'll grant you that a class isn't an anonymous function, arguably it's the same with lambdas that aren't as powerful as proper function defs.
But I'm not sure this is a problem. In fact, in some ways it may be advantageous e.g. static analysis.
I'd need a use-case for the anonymous closure, but a generator is a basic concept in python, so I son't think it's any trickier than a js function.
I know how in js there is a degree of 'binding' scope and hiding functionality in closures - I think in python (for better or worse) things would by convention be implemented differently.
As an aside, would you say js scope/closure approach is a bit similar to the approach in R?